Louis van Gaal has played the role of the professor all season and sometimes he can make us feel like students in the classroom. But, a week on from a goalless draw in Cambridge, one of the great educational centres of the world, he still has a lot learn about his team.

There were no signs of enjoyment or self-expression in that game and it looks like the players are weary of Van Gaal’s experimenting.

United enjoyed a good unbeaten stretch but there were never any dominant displays in that run. They ground out results and often looked laboured.

Gylfi Sigurdsson scores as Swansea City beat Manchester United on the opening day of the season

Louis van Gaal has experimented a lot with his team but they have failed to convince in any formation

Can you really say there was much of a difference in the level of performance between the 0-0 last week and the opening-day defeat by Swansea?

It’s no secret Van Gaal wants to play with a back three but it’s so obviously flawed that even the fans feel compelled to tell him so. When he changed things at QPR, it looked like the penny had dropped. They stuck with a back four against Cambridge but with little success.

It will be interesting to see if he reverts to a 3-5-2 on Saturday because United are facing a team who love playing against a back three. Leicester’s best performances of the season have come against sides that play three at the back.

They tore United apart in that stunning 5-3 win and produced a fine comeback from 2-0 down to draw at Liverpool. Wide men such as Jeff Schlupp and Riyad Mahrez are the perfect players to bomb forward and expose gaps left by defenders playing in a three. Mahrez will be missing — he is with Algeria at the Africa Cup of Nations — but Schlupp can cause United problems.

Manchester United's players look dejected during their recent draw with Cambridge United

Michael Carrick walks off the pitch while the Cambridge players celebrate after the FA Cup clash

Leicester City exposed Manchester United the last time they played back in September

I played in a back three many times and if you are the widest defender you feel vulnerable.

It’s a system that places disproportionate demands on the wing backs to cover more ground than anyone else. If they don’t drop back, the widest defender has to move across to cover the space. That leaves huge gaps for the opposition to fly into, as our graphic shows.

When you’re out of possession it drags your team shape all over the place and, unless your wing backs drop deep, it leaves you short of defenders in the box. United have struggled to get it right, QPR abandoned it after a few games and Liverpool only seem to be coming to grips with it now.

Nigel Pearson has used the system in the past, so he knows just how to exploit it, but United have had enough time to make it work. They have a squad capable of competing in four competitions, but are in only two. They have played 10 games fewer than Chelsea and Liverpool, nine less than Arsenal and eight fewer than Man City.

Jamie Vardy celebrates scoring to put Leicester City in the lead at the King Power Stadium

Van Gaal has persisted with playing three at the back despite the problems he has faced

That means more time on the training pitch but Van Gaal overcomplicates things. He clearly feels he knows best, but does he? A lot of United players have been used in multiple positions, which makes it harder to know their role.

Wayne Rooney has played up front, off the front and in midfield, Angel di Maria has played in midfield, off the front and as a striker and Daley Blind has been used all over the place. Then there are the defenders who have had to plug all sorts of gaps. However, things can change.

At this stage last season, Liverpool had only three points more than United do now. And, with the advantage of playing only once a week, Brendan Rodgers’ side came into their own in the second half of the campaign — they were absolutely flying. United can follow suit.

Van Gaal arrived at United saying he could win the title this season. He is a long way from achieving that but if he can finally settle on a preferred system that suits these players then things will improve. It’s time for him to stop experimenting and find the right formula to make United great again.

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